Apparatus for treating a continuous web or film of material with a liquid



y 196$ u. FRAUCHIGER ETAL 3,457,898

APPARATUS FOR TREATING A CONTINUOUS WEB OR FILM 0F MATERIAL WITH ALIQUID Filed June 22, 1967 4 Sheets-Sheet 1 In'n S m TmM WWR I E VWH CNA, IRE FB H R 3 L0 UJ ATTORNEYS y 29, 1969 u. FRAUCHIGER ETAL 3,457,898

APPARATUS FOR TREATING A CONTINUOUS WEB 0R FILM 0F v MATERIAL WITH ALIQUID Filed June 22, 1967 4 Sheets-Sheet 2 F IG. 3

INVENTORS ULRICH FR9UC HlGER JOSEPH BECHEIRAZ ATTORNEYS.

3,457,898 APPARATUS FOR TREATING A coNTINuoUs WEB 0R FILM OF Filed June22, 1967 y 29, 1969 u. FRAUCHIGER ETAL MATERIAL WITH A LIQUID 4Sheets-Sheet I5 INVENTORS ULRICH FR AUCHIGER JOSEPH BE CHEIRAZ ATTORNEYSJuly 29, 1969 u. FRAUCHIGER ETAL 3,457,898

APPARATUS FOR TREATING A CONTINUOUS WEB OR FILM OF MATERIAL WITH ALIQUID Filed June 22, 1967 4 Sheets-Sheet 4 u INVENTORS H FRQUCHIGEKJOSEPH BECHEIRAZ ATTORNEYS United States Patent M 3 457 898 APPARATUSFOR TIQEATING A CONTINUOUS WEB 0R FILM 0F MATERIAL WITH A LIQUID UlrichFrauchiger, Winterthur, and Joseph Bcheiraz,

US. Cl. 118419 16 Claims ABSTRACT OF THE DISCLOSURE Apparatus fortreating webs or films of material, such, as paper, fabric orphotographic film comprises a distributor within a tank. The material tobe treated is led past the distributor from which treating liquid issuesthrough slit-like nozzles in turbulent motion. The distributor maycomprise a bank of orificed tubes each having at least two, andpreferably three, elongated spaced strip-like baffle plates therebelow,so arranged that the edges of the bafiie plates define between them thenozzles, or may comprise a pressure-tight vessel having channel means inits side, the mouths of the channel means defining the nozzles. Meansare provided for feeding the liquid to the distributor and forwithdrawing it form the tank. The material may pass down the tank andback past both sides of the distributor and be led at its lower end overa freely rotatable return roller. lets of treating liquid may bedirected into the gap between the material and the roller to cushion thematerial.

This invention relates to apparatus for treating continuous webs orfilms of material, such as paper or fabric webs, or photographic films,with a liquid.

Various methods and arrangements have already been proposed for treatingsheet or band material, such as paper and fabric webs, photographic filmand the like, with liquids that are in motion. For example, in one sucharrangement the continuous webs are-pulled through treating baths bymechanical conveying means and, ac-

cording to the intensity of interaction between the liquid and thesurface of the web that is desired, more or less intense motion isimparted to the treating liquid. For thus imparting motion to the liquidin a bath in relation to the surface of a material that is to be treatedthereby, devices such as agitators, vibrators, ultarsonic oscillators,nozzles and the like have already been used. Such nozzles are arrangedto discharge a continuous or pulsed stream of gas into the liquid andthe bubbles which then rise in the liquid are intended to generate localturbulent motion. In apparatus comprising means for continuouslyrenewing or circulating the treating liquid it has also been proposed tocontrive the circulating means in such a way that a large degree ofagitation is simultaneously produced in the bath.

However, all these prior arrangements have the defect that considerablepower must be expended to produce a sufficiently high degree of relativemotion between the liquid and the treated surface and that it is alsoimpossible to achieve a completely uniform distribution of the volume ofliquid contacting the surface as well as a uniform distribution ofliquid velocities.

It is therefore one object of the present invention to provide apparatusin which a relatively high velocity gradient can be generated betweenthe liquid and the treated surface. Another object of the invention isto reduce the required power consumption to a minimum.

3,457,898 Patented July 29, 1969 Yet another object of the invention isto ensure that the velocity distribution over large surface areas isuniform. This is a matter of major importance in cases in which therelative velocities between the liquid and the treated surface and theperiod of contact directly govern the intensity of the effect that isdesired, as is the case for instance in dyeing processes or in theprocessing of an exposed photographic film.

According to the present invention there is provided apparatus fortreating a continuous web or film of material with a liquid, comprisinga tank for receiving said liquid, means for admitting liquid into thetank, means determined path, the arrangement being such that, when theapparatus is in operation, the liquid issues from said nozzles inturbulent flow and is directed on to the traveling material.

Preferably the distributor means comprises a plurality of orificeddistributor tubes placed with their axes parallel and alongside thepredetermined path of travel of the material, and the slit-like nozzlesare preferably constituted by the edges of a plurality of superposedelongated strip-like plates disposed in parallel the one behind theother, each plate, with the exception of the last plate remote from theorifices in its associated distributor tube, being provided with atleast one opening in the path of the jets of liquid issuing from theorifices, the cross-sections of said openings extending at least partlyover solid surface parts of the following plate in the path of the jets.

In order to enable the invention to be more readily understood,reference will now be made to the accompanying drawings, whichillustrate diagrammatically and by way of example some embodimentsthereof, and in which:

FIG. 1 is an elevational section of a tank equipped with a distributor,the section being taken in a plane parallel to a bank of tubes whichtogether 'formjthe distributor,

FIG. 2 is a section taken on the line IIII in FIG. 1,

FIG. 3 is a section of a detail in FIG. 2, drawn to a larger scale,

FIG. 4 is a part sectional perspective view ofanother distributor, and

FIG. 5 is a section taken on the line V-V in FIG.

Referring now to FIGS. 1 to 3 of the drawings, there is shown adistributor, generally indicated by 1, which is vertically built into atank 2. The distributor comprises tubes 3a, 3b, 3c, 3d and 32 forming abank of axially parallel coplanar tubes parallel to the path of travelof a material to be treated as indicated in FIG. 2 by a thin line 4.Each tube is formed with a row of orifices 5 situated on at least oneline of intersection of the tube with the plane containing the axes ofthe tubes in the-bank.

Each row of orifices is faced by baflles or flow-deflecting elementswhich in the illustrated embodiment have the form of three parallelrelatively spaced elongated strip like bafile plates 6, 7 and 8 facingthe row of orifices and placed the one behind the other. The two plates6 and 7 nearest the row of orifices are each formed with a slot 9 and 10respectively, the longitudinal centre lines of the slots being likewisecontained in the plane containing the tube axes and the rows of orifices5, but the plate 8 furthest away from the orifices is not formed withsuch a slot. The size of the slots, particularly their width, de-

creases from plate to plate with increasing distance of the plates fromthe orificed tube which they face. In a preferred embodiment of thisarrangement the plates 6, 7 and 8 are transversely arched with theirconcavities facing the associated orificed tube, as is clearly shown inFIG. 3 which also shows the general arrangement and the relative sizesof the slots 9 and 10.

It should also be understood from FIGS. 1 and 2, that the path of travel4 of the treated material extends along both sides of the bank ofdistributor tubes, the material being taken over a return roller 11.

Below the bottom distributor tube 3e of the bank, i.e. between this tubeand the return roller 11 for the travelling material 4 is a suction tube12 which extends parallel to the distributor tubes 3a to Sc, and whichis formed at its periphery with orifices having a total opencross-section at least equal to the total open cross- 20B. Each of thesetwo chambers has a separate consection of the orifices in all thedistributor tubes in the bank. Preferably, and as illustrated, theorifices in the suction tube align along the bottom generator of thetube.

The distributor 1, the baflle or deflector plates 6, 7, and 8, thesuction tube 12 and preferably the roller 11 for the treated materialform a structural entity built into the tank as a unit.

In the operation of the apparatus just described, the tank 2 is filledwith the treating liquid and the material to be treated is fed along thepath 4 and around the return roller 11 by conventional means not shownin the drawings. The treating liquid is admitted to the tanks via amanifold 33 which communicates with one end of each of the tubes 3a-3ewhich are all closed at their other ends. The liquid issues as a seriesof jets from the orifices 5 and some of its strikes the baffle plate 6causing turbulent motion of the surrounding liquid which flows over theedge of the plate 6 to be directed onto the travelling material. Some ofthe jet of liquid passes through the aperture 9 to strike the baflleplate 7 while some of the jet passes through the aperture 10 to strikethe plate 8. The

liquid striking the plates 7 and 8 causes turbulent motion of thesurrounding liquid so that the liquid, in turbulent motion issues fromthe slit-like nozzles defined by the edges of the plates 6 and 7, and 7and 8 respectively to be directed onto the travelling material. Theliquid is withdrawn from the tank by the suction pipe 12.

The distributor illustrated in FIGS. 4 and 5 comprises a pressure-tightvessel which has two side walls 21 and 22 which are parallel to theplanes in which a material to be treated travels. Each of these walls isformed with open channels 23 which extend crosswise of the path 4a, 4bof the travelling material. A wall portion 23a of these channelsprojecting substantially perpendicularly inwards from the walls 21 and22 of the tank is formed with a row of orifices 24. Inside each channela narrow strip-shaped part 23b of the internal channel wall whichlikewise projects substantially perpendicularly from the distributorwalls 21 and 22 faces the orifices. Each channel is completely opentowards the path of the treated material. This is an important featurebecause the presence of obstructions of any kind might operate to reducethe turbulence generated inside the channels.

A returnroller 11 and one chain wheel 25 is all that can be seen in FIG.4 of means for conveying the material to be treated. These elements aredirectly mounted on the pressure-tight vessel and thus togethertherewith form a structural unit which can be built into a tank inexactly the same way as the distributor unit shown in FIGS. 1 and 2. Asecond chain wheel (not shown) is mounted at the front end of the returnroller 11 in FIG. 4. However,

the two chain wheels and the return roller are not coupled butindividually rotatable. The chain wheels deflect a chain (not shown) forentraining the treated web of material.

The pressure-tight vessel illustrated in FIG. 4 is horizontally dividedinto two separate chambers 20A and nection for the supply of a treatingliquid under pressure. In the illustrated embodiment the connection intothe upper chamber 20A is indicated at 26, whereas that for the lowerchamber is a pipe 27 which extends downwards through the upper chamberinto the lower chamber. The top of the pressure-tight vessel is furtherprovided with a cover 28 which tightly closes an inspection and cleaningwindow.

As shown in FIG. 5, the pressure-tight vessel according to FIG. 4 isintended to be built into a tank 2 (similar to the tank 2 shown in FIG.2) which is fitted with a separate connection for the extraction of theliquid, or with an overflow. Alternatively, the pressure-tight vesselitself might be further subdivided to form at least one suction chamber.

Closely above the return roller 11 the bottom chamber 20B which is shownin cross-section in FIG. 5 is formed with a semi-cylindrical convexbulge 29 extending parallel with and lengthwise of the return roller.This convex bulge contains a row of orifices 30 along the length of theroller 11. In relation to the roller 11 these orifices 30 are sodisposed that the jets issuing therefrom are directed into thewedge-shaped gap between the roller surface and the surface of thematerial 4a running onto the roller. These jets likewise consist of thetreating liquid which can be introduced into chamber 20B through thepipe 27 at a pressure above that of the liquid entering the chamber 20Athrough the pipe 26. The jets impinge on the roller surface at an acuteangle, nearly tangentially, and they therefore operate both to drive thefreely rotatable roller in the direction of travel and to create betweenthe roller surface and the treated web of material a cushion of liquidwhich eliminates or at least reduces the resistance generated by thedeflection of the material, prevents the material from being damaged bycontact with the return roller and increases the effect of thetreatment. These elfects can be further assisted by a deflector strip31.

v The distance of the jet orifices 30 from the surface of the roller 11is only a fraction of the roller diameter, preferably said distancebeing between 1 and 10 mm.

The present method of guiding the treated material over a freelyrotatable roller which is jet driven, and upon which a liquid cushion isformed, may be used with advantage wherever it is desired to deflectcontinuous webs or films of material in a liquid.

. The directions of pressure and suction in the pipe means and thedirections of the jets are indicated in the drawings by arrows. Arrowsalso show the directions of travel of the treated material and thedirection of rotation of the roller.

What is claimed is:

1. Apparatus for treating a continuous web or film of material with aliquid, comprising a tank for receiving said liquid, means for admittingliquid into the tank, means for withdrawing the liquid from the tank,means for conveying the material to be treated through the tank along apredetermined path, distributor means including orifices for said liquidpositioned within the tank adjacent to said predetermined path andconnected to the means for admitting liquid into the tank, and bafflemeans arranged facing the orifices of said distributor means anddisposed at a steep angle to said predetermined path, said orifices aredisposed for directing jets at a steep angle onto said baffle means, sothat, when the apparatus is in operation, the liquid issues from saidbaflle means in turbulent flow and is directed onto the travellingmaterial.

2. Apparatus as claimed in claim 1 wherein the angle between the jetsand the baffle means is about 3. Apparatus for treating a continuous webor film of material with a liquid, comprising a tank for receiving saidliquid, means for admitting liquid into the tank, means for wthdrawingthe liquid from the tank, means for conveying the material to be treatedthrough the tank along a predetermined path, distributor means includingorifices for said liquid positioned within the tank adjacent to saidpredetermined path and connected to the means for admitting liquid intothe tank, and baffle means ar ranged facing the orifices of saiddistributor means and disposed at a steep angle to said predeterminedpath, said orifices are disposed for directing jets at a steep angleonto said baffle means, said distributor means comprises a plurality ofdistributor tubes placed with their axes parallel and forming a bankalongside said predetermined path, portions of each tube definingorifices which are arranged in a row, said baffle means comprises atleast two superimposed elongated strip-like baffle plates arranged belowsaid orifices each baflle plate being apertured except for the lowermostbafile plate, the arrangement of the baffle plates being such that thespaces between the edges of the baffle plates define slit-like nozzles,at least some of the treating liquid being intended to pass from saidorifices through the aperture in each plate and to issue in turbulentflow from the slit-like nozzles defined by the edges of the baffleplates.

4. An apparatus as claimed in claim 3 wherein there are at least threesuch bafile plates, the aperture in any bafile plate being wider thanthat in the baffle plate immediately below it.

5. Apparatus as claimed in claim 4 wherein the tubes and baffie platesare arranged in a vertical bank.

6. Apparatus as claimed in claim 5, wherein the means for withdrawingthe liquid from the tank includes an orificed suction tube extendingparallel to and below the distributor tubes.

7. Apparatus as claimed in claim 6 wherein the distributor means, thesuction tube and the means for conveying the material through the tankare combined in a structural assembly vertically mounted as a unitinside the tank.

8. Apparatus as claimed in claim 4 wherein the sides of the bafileplates facing the associated distributor tube are concavely arched.

9. Apparatus for treating a continuous web or film of material with aliquid, comprising a tank for receiving said liquid, means for admittingliquid into the tank, means for withdrawing the liquid from the tank,means for conveying the material to be treated through the tank along apredetermined path, distributor means for said liquid positioned withinthe tank adjacent to said predetermined path and connected to the meansfor admitting liquid into the tank, said distributor means comprises apressure-tight vessel, at least one side wall of said vessel lyingsubstantially parallel to said predetermined path, orificed channelmeans let into each side wall of the vessel extending in a directiontransverse to the intended direction of travel of the material, theorifices in said channel means communicating with the interior of thevessel and are disposed for directing jets at a steep angle onto an areaof the channel wall which is disposed at a steep angle to saidpredetermined path, so that, when the apparatus is in operation, theliquid issues from the mouths of the channel means in turbulent flow andis directed onto the travelling material.

10. Apparatus as claimed in claim 9, wherein the angle between the jetsand said area of the channel wall is approximately 90.

11. Apparatus as claimed in claim 9, wherein the area of the channelwall which faces said row of orifices is concavely formed.

12. Apparatus for treating a continuous web or film of material with aliquid, comprising a tank for receiving said liquid, means for admittingliquid into the tank,

means for wthdrawing the liquid from the tank, means for conveying thematerial to be treated through the tank along a predetermined path,distributor means for said liquid positioned within the tank adjacent tosaid predetermined path and connected to the means for admitting liquidinto the tank, and bafile means arranged facing the orifices of saiddistributor means and disposed at a steep angle to said predeterminedpath, said orifices are disposed for directing jets at a steep angleonto said baffle means, said predetermined path extends from the top ofthe tank to the bottom and back to the top, the return of the travellingmaterial inside the tank being effected over a freely rotatable rolleralong the length of which further jet orifices are disposed fordirecting jets into the wedge-shaped gap between the surface of theroller and the surface of the material running over the roller.

13. Apparatus as claimed in claim 12, wherein the distance of saidfurther jet orifices from the surface of said roller is only a fractionof the roller diameter.

14. Apparatus as claimed in claim 13, wherein said distance is between 1and 10 mm.

15. Apparatus as claimed in claim 12, wherein said further jet orificesare formed in a quasi-tubular distributor extending parallel to thereturn roller, said distributor being fitted with a longitudinaldeflector projecting substantially tangentially towards the rollersurface in such manner that the last mentioned jet orifices arecontained within the gap defined between said deflector and the rollersurface.

16. Apparatus for treating a continuous web or film of material with aliquid, comprising a tank for receiving said liquid, means for admittingliquid into the tank, means for wthdrawing the liquid from the tank,means for conveying the material to be treated through the tank along apredetermined path, distributor means for said liquid positioned withinthe tank adjacent to said predetermined path and connected to the meansfor admitting liquid into the tank, said distributor means comprises apressure-tight vessel, at least one side wall of said vessel lyingsubstantially parallel to said predetermined path, orificed channelmeans let into each side wall of the vessel extending in a directiontransverse to the intended direction of travel of the material, theorifices in said channel means communicating with the interior of thevessel and are disposed for directing jets at a steep angle onto an areaof the channel wall which is disposed at a steep angle to saidpredetermined path, said predetermined path extends from the top of thetank to the bottom and back to the top, the return of the travellingmaterial inside the tank being effected over a freely rotatable rolleralong the length of which further jet orifices are disposed fordirecting jets into the wedge-shaped gap between the surface of theroller and the surface of the material running over the roller.

References Cited UNITED STATES PATENTS 1,579,003 3/1926 Koch 118-429 X3,192,845 7/1965 Schmidt 89 3,310,062 3/1967 Little 6862 X 3,344,729 10/1967 Kitrosser 95-89 WALTER A. SCHEEL, Primary Examiner JOHN P.MCINTOSH, Assistant Examiner U.S. Cl. X.R. 6862; 118429

